EP 1 498 586 B1 discloses an exhaust gas treatment device of a type defined in the introduction, having a housing that can be connected to an exhaust system. At least one exhaust gas purification insert having an insert housing that is open at the end is arranged inside the housing. At least one exhaust gas purification element such as a particulate filter or a catalytic converter element is arranged in the insert housing. For mounting this exhaust gas purification insert in the housing, the housing has at least one insert bracket which has at least one mounting opening. An end section of the insert housing is supported on the opening edge of the mounting opening in a ring.
With the known exhaust gas treatment device, the respective opening edge is designed to be cylindrical and is provided with a predetermined constant cross section. The end section of the respective exhaust gas purification insert is also designed to be cylindrical and complementary to the former, so that the respective exhaust gas purification insert can be inserted axially with said end section into the opening edge of the respective insert bracket. It is advantageous here that the dimensions and shaping of the end section can be performed independently of the dimensioning of a housing jacket of the insert housing connected to the end section. In this way, the end sections may always be manufactured to fit the opening edges, whereas the respective insert housing can be adapted independently to the respective exhaust gas purification element whose manufacturing tolerances may be subject to a relatively great scattering.